Tires having retroreflective strips around their sidewalls, e.g., as disclosed in U.S. Pat. Nos. 3,382,908 (Palmquist et al.) and 3,449,201 (Palmquist et al.), have found acceptance, particularly for use on bicycles and motorcycles, to provide a measure of safety when the cycle is operated after dark. Such tires are typically constructed by adhering parallel strips of an uncured elastomer such as neoprene rubber supporting a layer of retroreflective elements to an unvulcanized tire casing. The tire casing is then vulcanized in a tire mold to form a completed tire having a U-shaped cross-section with the strips supporting the retroreflective elements forming a unified or integral part of the vulcanized tire casing.
Examples of strips useful for such purposes are disclosed in the aforementioned U.S. Pat. Nos. 3,382,908 and 3,449,201. These patents disclose thin sheet materials comprising an elastomeric support layer with a monolayer of retroreflective elements embedded therein, wherein the support layer or at least a back stratum thereof is a vulcanizable elastomer which is compatible with the elastomer of the tire side wall.
While such sheet material may achieve a strong bond to the tire side wall after vulcanization, due to their thin construction and narrow widths to which they are typically cut they may tend to stretch too easily and therefore be difficult to work with during fabrication of the tire. For instance, such sheet materials may tend to have such a low breaking force that they may easily break when subjected to the tensile forces encountered during fabrication, particularly after being cut into strip form, and even when they withstand such forces without breaking, the sheet materials may not be sufficiently elastic to substantially recover their original dimensions, thereby spoiling the final appearance on the tire.